Drew Karp. Can't recall a single book of his that had a happy ending, but I enjoyed them and his other works.
I also admire my friend Monica, Endy, Adena and a few others.
I can also tell you who I don't admire as a writer. Brandon Rhea.
:CSly
Orson Scott Card. He's like the Chick-fil-A of the literary world.:CHappy
But in all seriousness I'm going with Pros' answer to this particular question. Just add Hemingway, Fitzgerald, Dostoyevsky, Asimov, Tolkien, and Frank Herbert.